Telephone-transmitter



(No Model.) V 2 Sheets-Sheet 1. I

' J-. W. B'ONT'A.

- TELEPHONE TRANSMITTER.

Patented Nov. '9

[NVEN/OR A T T ORYVE Y 2 Sheets- -Sheet 2.

(No Model.)

J. WQBONT'A. TELEPHONE TRANSMITTER.

No. 352,179. Patented Nov '9, 1886.

JNVENTOR,

A TT'OR/VE y UNITED; STATES PATENT OFFICE,

JAMES. W. BONTA, OF PHILADELPHIA, PENNSYLVANIA.

TELEPHONE-TRANS MITTER.

SPECIPIC'ATION forming part of Letters Patent No. 352,179, datedNovember 9, 1886.

v Application filed March 11,1886. Serial-No.194fi04. (No model.)

To all whomdt may concern.-

Be it known that 1, JAMES W. Bonrma citizen of the United States,residing at Philadelphia, in the county of Philadelphia and State ofPennsylvania, have invented certain new and useful Improvements inTelephouic Transmitters, of which the following is a specifica tion,reference being had therein to the accompanying drawings, wherein-Figurel is a sectional elevation of atelephonic transmitter embodying myimprovements in the most desirable form. Fig. 2 is a like view of samein'its simplest form. Fig. 3 is a like view of modification of same, andFig. 4 is a detail elevation of loose ball or electrode and supportingplate or table.

My invention has relation to telephonic transmitters of the form havinga loose ball or electrode, an adjustable carbon or other table or-blockfor supporting the ball, and mechanism for elevating, lowering, andtilting the table to vary the initial contact-pressure ofthe electrodes;and it has for its object to dispense with the elevating, lowering, andtilting ball or loose electrode holder orplate and substitute therefor afixed plate so constructed and having tension devices, whereby theinitial contact-pressure between the electrodes isva-fl ried as desiredwithout tilting or elevating and depressing said plate, as hasheretofore been done.

My invention accordingly consists of the combination, construction, andarrangement of parts, as hereinafter described and claimed.

A represents a transmitter case or box having a removable front, a,provided with a carbon diaphragm to the box I do not herein claim, as itis reserved for the subject of a future application.

To the outer end of standard I) is pivoted a depending bar, O,-having aknee or bend, as shown at c. To the upper part of the bar 0,

and on its side next to the diaphragm, is fastened a thin strip orplate, D,'to the lower end of which is secured a block, E, of carbon oranalogous or other suitable material, having in its front and top sidesa concavity or oval or other similar recess or chamber, e, for thereception of a loose carbon ball or electrode, F, which contacts withelectrode b or the dia phragm, as shown. The strip or plate D ispreferably slightly elastic, and, if desired,

may .be adjustable oubar 0 by means of the rolls, or rides up and downthe inclined or a curved sides 6 of the recess or chambere, to assumeits position relative to such adjustment for varying itscontact-pressure with the diaphragm or its electrodes,and thisadjustment or variation of contact-pressure is consequently made withoutmoving the block or plate E.

If desired, the tension or adjusting devices for block E maybe dispensedwith, as shown in Fig. 2, and instead of fastening the strip or plate Dto the bar 0 or to the caseA, it may be pivoted to aswiveled connection,h, on the end of ascrew, h, as illustrated in Fig. 3, so that the blockcan be raised or lowered to place the ball in the center of thediaphragm. In this case a fork or guide engages with the block to keepit from turning, and the contact-pressure of the electrodes is constant,as it also is when the construction shown in Fig. 3 is used.

Any suitable inductorium, I, may be used, the primary one of whichincludes the diaphragm B or its electrode b, the ball F, plate or blockE, and battery 3, and the secondary forms part of the line.

I do not broadly claim in this application the means for verticallyadjusting the support for the loose electrode with varying theinclination of the support, as that forms the subjectmatter of aseparate application filed on even date with this and numbered 194,801.

What I claim is 1. In a telephonic transmitter, a diaphragm, a looseball or electrode, and a block or plate having a curved or oval recessor chamber, 0, substantially as shown and described.

2. In a telephonic transmitter, a diaphragm,

a loose ball or electrode, a block, E, having 4. The combination ofdiaphragm B, loose 1'5 ball or electrode F, block E, having chamber 6,pivoted bar 0, supporting-block E, spring G, and set-screw 6substantially as shown and.

described.

In testimony whereof I affix my signature in 20 presence of twowitnesses.

JAMES W. BONTA.

W'itnesscs:

S. J. VAN Smvonnx, CHAS. F. VAN HORN.

